Carburetor



A. R. BAKER l Jan. 5, 1937.

GARBURET'QR Original Filed Sept. 9, 1932 Ww im Dm M A Patented Jan. 5, 1937 UNITED STATES PATENT oFFlcE CARBURETOR Application September 9, 1932, Serial No. 632,440 Renewed August 22, 1935 9 Claims.

This invention relates to improvements in carburetors and particularly to means for controlling the fuel mixture in the carburetor. It is filed as a continuation in part of my application, Serial No. 457,362, filed May 29, 1930, which has matured into Patent No. 1,877,117, dated September 13, 1932, and to cover further developments in the carburetor forming the subject matter of said patent. p

An object of the invention is to provide a carburetor adapted for use in engines having a high compression.

Referring to the accompanying drawing, which is made a part hereof and on which similar reference characters indicate similar parts,

Figure 1 is a plan view of a portion of a carburetor having my invention applied thereto,

Figure 2, a vertical section substantially on line 2--2 of Figure 1,

Figure 3, a section on line 3-3 of Figure l,

Figure 4, a section on line 4-4 of Figure2, and

Figure 5, a section on line 5-5 of Figure 1.

' A compression ratio of 4 or 5 to 1 is the normal compression. A 6 to l ratio is considered high compression. A 7 to 1 is called super-compression. The carburetor of this application deals primarily with super-compression. y

In carburetors now on the market di'iculty is experienced with high compression engines. If the engine is operating under exceedingly high compression and the throttle is opened suddenly.

or to a very great extent a heavy fuel charge will be drawn into the engine which will give a powerY o-ut of proportion to the demands on the engine, the result of which is that there is a loss of eiciency. By my improved carburetor means are provided for delivering a gradually increasing volume of fuel to the engine and while the volume of the fuel charge is gradually increasing the fuel mixture is enriched and chilled to the point where the excessive charge to the engine is properly conditioned.

In the drawing numeral I!) indicates the carburetor casing which may contain a fuel well and a float chamber of the usual construction. The throttle valve casing II contains a sleeve or Venturi Valve I2 which may be operated by any suitable mechanism not shown. This valve pro- AVides a venturi about a normally fixed cone shaped member I3. Air and gasoline or other fuel are sucked in through and around the tube I4 respectively and delivered under reduced pressure into a hot cap I5 which is positioned in l the path of the exhaust gases from the engine whereby it is simultaneously sprayed and heated to a temperature above that required to fire a normal fuel charge. The fuel and air areso proportioned as to result in a mixture too rich to fire. Surrounding the nozzle arrangement I4 is a spiral IB which causes the vaporous fuel to travel in a spiral path in contact with the walls of the hot cap. Any drop of liquid fuel which may have formed, will form into a thin film, leak between the periphery of the spirals and the walls of the hot cap and thus become vaporized and pass to a channel I'I and a chamber I3 formed in the upper end of the cone shaped member I3 from the chamber I8. The fuel mixture then passes through radial passages I9 where proper air for combustion is added and then into the chamber 20 from which it is drawn into the suction of the engine. The cone-shaped element I3 has a cylindrical extension 2| which is slidable in a bore in the casing 22. l To the lower side of' the cone I3 is attachedan operating stem 23. In a chamber adjacent the valve arrangement just described is mounted a member 24 within which slides a piston 25. A Valve 2E is positioned in the bottom of the chamber 24 through which valve gasoline or other liquid fuel may pass from the space 2.1 into the space 28 beneath the piston 25. 'Ihe piston 25'has an arm or bracket 29 secured to its upper end b y means of a screw 39,'

and passes down alongside of the casing and-is notched as shown at 3l which notch engages over a lever'32. This lever is pivoted on a pin'33 which is fixed in the casing of the carburetor and extends forwardly and engages a notch at 34 in the side of the sleeve valve 35. The tubular member 24 has an annular groove 3B at its upper end into which groove engage the forks of an operating shaft 3I. This shaft is notched at 39 soas to permit the lever 32 to extend through it and is further notched at 39. Into this latter notch engages a bent over or hooked portion 49 depending from the underside of a lever 4I. The lever 4I is pivoted at 33 and its free end engages between collars 42 on the stem 23. The piston 25 is provided with an axial bore 43, the upper end of which receives an adjustable screw 44 by means of which screw passage of fluid through the bore is controlled. y l

As shown in detail in Figure 5 a valve 48 has a depending stem 49 carrying a flange 59 which is engaged by some portion of the sleeve valve I2 as this valve is opened, the valve operating against the tension of a spring 5I which normally tends to hold it closed. As will be apparent the valve 48 is opened upon each opening of the Valve I2. Adjacent the valve 48 is another valve goes in through the Venturi tube as the steam 23 n is depressed. This enriches the fuel charge. The

liquid fuel which passes through the valves 48V and 52 is carried into the Venturi valve through aV tube 51. This tube has a small bore 58 through which air is sucked to emulsify and atomize the liquid fuel which is delivered into the main air stream going through the venturi. y

In operation the air and liquid fuel are `drawn in through and around the tube I4 and sprayed into the hot cap/,I5 The fuel in this condition contains air with a relatively largevolume of liquid fuel at reduced pressure, Vthe combined mixture of which is too rich to be red. The combined mixture is heated to a temperature above the ignition point of a normal explosive fuel charge in the hot cap I5. As the mixture passes out of the hot cap, it is caused to travel in a spiral path and thus brought into contact with the side 45 of the hot Lcap which side is toward the exhaust gases which are at a highV temperature and thus assist in vaporizing any liquid elements in the fuel charge. When the sleeve valve 35 is depressed by the operator the throttle is opened so that air is drawn in around the conical surfaces I3 and mixed with the 'fuel charge from the hot cap and delivered to the engine. In carburetors heretofore known depressing the sleeve valve delivered an excessive fuel charge to the engine. Under high compression engines this sudden delivery of an excessive fuel charge was highly objectionable. My improvement consists in providing means `for gradually admitting the charge. As the sleeve valve 35 is depressed it pulls down` on the lever 32. This lever engages the bracket 29 and depresses the piston 25. kThe chamber 28 is lled with gasoline which has entered through a channel 46, and through valve 26 into the chamber 28. As the piston 25 is depressed therefore it carries down with it the cylindrical member-24 through the bracket 31 engaging the lever 4 I and this depresses the'stem 23. The spring 41 allows additional opening of the Venturi valve. As soon as the member 24 has reached the limit of its downward travel it begins to rise as the liquid fuel in chamber 28 is forced out through the port 43. The needle valve 44 controls the rate of escape of this liquid. As the member 24 rises it lifts the stem 23 to open the throttle gradually and thus deliver sullicient air to the fuelcharge. While the valve 35 is depressed and the stem 23 is also depressed the suction fromv the engine through ports I9 creates an increased suction at the nozzle I4. This increases the fuel drawn to lthe hot cap and further enriches the fuel mixture. dampen the mixture. The valve stem 23 is automatically lifted so that the air to the enginefwill gradually increase. This is as it should be. It should be noted that in operating with high compression engines that the fuel charge delivered by my carburetor will be at a much lower temperature than charges delivered by carburetors as now known, in that, the evaporation of the'richv fuel mixture Will tend to reduce the The result of this action is to temperature of the fuel charge. Since the throttle is only partially open the amount of fuel delivered to the engine will` likewise be limited.

The compression spring 41 has an important function. This spring is seated in a depression in the casing and bears against the lower side of the lever 4I adjacent the pivot pin 33. 'Ihe pivot pin 33 enters an elongated slot in the end of the lever 4I. The purpose of the spring is as follows:

The liquid fuel in the chamber 28 being noncompressible, theflever 4I fulcrums kat point 40 and allows the deflector head I3 to move up and down'according to the engine pulsation and to put a substantially uniform suction on the fuel passing through the nozzle I4 and when the throttle valve I2 is depressed, the deflector head I3 is depressed with it through the lever mechanism. Unless there is a cushion it puts too great suction on the nozzle point I4 and enriches the mixture too much. The buffer spring 41 is made the right tension to enrichen the mixture entering the motor at that particular throttle opening. It may be found desirable for better refinement in control to provide means for varying the tension of the spring 41.

An analysis of the fuel chargefin the lhot cap I5 shows the presence of an appreciable amount of non-condensable gas or gases.V Present among these gases are carbon monoxide and hydrogen.

to the high temperature to which fuel in the hot cap I5 is raised- Operating under high compressionor supercompression the temperature. of this gas will bevention and therefore I do not limit myself to. what is shown in the drawing and described in4 the specification, but only as indicated by the appended claims.

I claim:-

1. In a carburetor having means for mixingI the liquid fuel and air to formv a mixture which is too rich to re, a valve for controlling admission of air to said mixture, said valve comprising two movable elements, one movable relative to the other, and means for moving both of said for stopping movement of one of said elements after the valve has moved to an open position, substantially as set forth.

2. A carburetor having` means for mixing and simultaneously heating liquid fuel and cold air tol create a fuel mixture too rich to fire, a valve Vfor admitting air to said mixture, means for operating said valve, and means for delaying opening of the valve to gradually increase the supply of cold air to said mixture when the manually oper. able means is operated, substantially as set forth.

3. Means for preparing a proper fuel charge for an internal combustion engine comprising means for mixing and atomizing liquid fuel` and air and simultaneously forming a mixture which is too rich to nre and heating the mixture to a temperature above the ignition point of a normal explosive fuel charge, a valve for supplying air to said fuel charge and for gradually controlling the ao It is believed the formation of these gases is due 5,5.. elements at the initial opening of the valve but i increase of the supply of air automatically and simultaneously adding to the supply of air a predetermined amount of atomized liquid fuel, substantially as set forth.

4. A carburetor adapted to supply a non-detonating charge to an internal combustion engine operating under super-compression comprising means for mixing cold air and fuel to form a mixture too rich to re, simultaneously heating the mixture to a temperature above the ignition point of a normally explosive charge, and means for supplying conditioning air to the fuel charge and means for supplying the fuel charge gradually as the throttle valve is open, and means for supplying atomized liquid fuel to the air to further enrich the air in fuel as it is supplied to the rich, highly heated fuel charge previously prepared, substantially as set forth.

5. In a carburetor having means for mixing fuel and air to form a mixture too rich to fire, means for heating said mixture to a temperature at which an explosive charge would be ignited, a valve for controlling the admission of air to said rich mixture to create a fuel charge of the desired richness, and means for limiting operation of said valve to effect a gradual addition of air to the said fuel mixture, and means operable by said valve for supplying an additional volume of fuel to further enrich the fuel charge, substantially as set forth.

6. In a carburetor having means for mixing fuel and air to form a mixture too rich to fire, means for heating said mixture to a temperature at which an explosive charge would be ignited, a valve for controlling the admission of air to said rich mixture to create a fuel charge of the desired richness, means for limiting operation of said valve to effect a gradual addition of air to the said fuel mixture, means operable by said valve for supplying an additional volume of fuel to further enrich the fuel char-ge, and means for absorbing impulses of the engine to prevent fluctuations in the said valves thereby maintaining the fuel and air supply of a relatively even flow, substantially as set forth.

7. In a carburetor having means for mixing liquid fuel and air to form a rich mixture, a valve for controlling admission of air to said mixture, said valve comprising a valve disk and a valve seat, means for moving the valve disk and valve seat at the initial opening of the valve but for moving the valve disk relative to the valve seat to completely open the valve.

8. In a carburetor having means for mixin-g fuel and air to form a rich mixture, a valve for controlling the admission of air to said fuel mixture to create a mixture of the desired richness, means for supplying additional fuel to the air to enrich the mixture and means for absorbing impulses from the engine of the vehicle to insure a relatively even flow of the fuel.

9. In a carburetor having means for mixing liquid fuel and air to form a rich mixture, a valve for adding air to said mixture, said valve comprising two movable elements, one movable relative to the other, the space between the elements determining the extent of opening of the valve, both of said elements being movable at the beginning of opening of the valve and means for restoring one of the elements to its initial position after a predetermined period after movement of the elements together.

ARTHUR R. BAKER. 

